[OneBot] Try to support node

Lagrange.Core/Message/MessageBuilder.cs

@@ -82,6 +82,22 @@ public MessageBuilder Image(byte[] file)
         return this;
     }
 
+    public MessageBuilder File(byte[] file, string fileName)
+    {
+        var fileEntity = new FileEntity(file, fileName);
+        _chain.Add(fileEntity);
+
+        return this;
+    }
+
+    public MessageBuilder File(string filePath)
+    {
+        var fileEntity = new FileEntity(filePath);
+        _chain.Add(fileEntity);
+
+        return this;
+    }
+
     public MessageBuilder Add(IMessageEntity entity)
     {
         _chain.Add(entity);

Lagrange.OneBot/Core/Message/Entity/ForwardSegment.cs

@@ -12,12 +12,15 @@ public ForwardSegment() : this("") { }
     [JsonPropertyName("id")] public string Name { get; set; } = name;
 }
 
-[SegmentSubscriber(typeof(MultiMsgEntity), "forward")]
+[SegmentSubscriber(typeof(MultiMsgEntity), "forward", "node")]
 public partial class ForwardSegment : ISegment
 {
     public IMessageEntity ToEntity() => throw new InvalidOperationException("Only Receive but not send");
 
-    public void Build(MessageBuilder builder, ISegment segment) => throw new InvalidOperationException();
+    public void Build(MessageBuilder builder, ISegment segment)
+    {
+        if (segment is ForwardSegment forward) builder.Add(new MultiMsgEntity(forward.Name));
+    }
 
     public ISegment FromEntity(IMessageEntity entity)
     {

Lagrange.OneBot/Core/Message/SegmentSubscriberAttribute.cs

@@ -1,9 +1,11 @@
 namespace Lagrange.OneBot.Core.Message;
 
 [AttributeUsage(AttributeTargets.Class)]
-public class SegmentSubscriberAttribute(Type entity, string type) : Attribute
+public class SegmentSubscriberAttribute(Type entity, string type, string? sendType = null) : Attribute
 {
     public Type Entity { get; } = entity;
 
     public string Type { get; } = type;
+
+    public string SendType { get; } = sendType ?? type;
 }

Lagrange.OneBot/Core/Operation/Message/MessageCommon.cs

@@ -19,7 +19,7 @@ static MessageCommon()
         foreach (var type in Assembly.GetExecutingAssembly().GetTypes())
         {
             var attribute = type.GetCustomAttribute<SegmentSubscriberAttribute>();
-            if (attribute != null) TypeToSegment[attribute.Type] = (ISegment)type.CreateInstance(false);
+            if (attribute != null) TypeToSegment[attribute.SendType] = (ISegment)type.CreateInstance(false);
         }
     }